Duct-installable heat exchanger



May 11, 1965 R. E. PIERCE 3,182,717

DUCT-INSTALLABLE HEAT EXCHANGER Filed Oct. 25. 1961 RCTUIN AIR l2 comma/2 SPRAY L IN V EN TOR. Aaamr P/ew:

BY M /(Q'% United States Patent 3,182,717 DUCT-INSTALLABLE HEATEXCHANGER Robert E. Pierce, Farmington, Mich., assignor to AmericanRadiator & Standard Sanitary Corporation, New

York, N.Y., a corporation of Delaware Filed on. 25, 1961, Ser. No.147,584 1 Claim. (Cl. 165-47) This invention relates to heat exchangersand particularly to improved mechanisms and arrangements for installingheat exchangers in sheet metal duct work, as for example in airconditioning systems. In certain air conditioning systems, particularlylarge commercial systems, there are provided in the air ducts certainauxiliary heat exchangers for tempering the air prior to itsintroduction into the rooms being serviced by the conditioning system.In the past these auxiliary heat exchangers have been installed byproviding each end face of the exchanger with outwardly projectingflanges having punched holes therein. Installation was accomplished bybuilding special duct sections with special out wardly projectingflanges, drilling holes in the flanges to mate with the aforementionedheat exchanger flange holes, and extending bolts through the matingholes. Such installation procedures required considerable on-the-joblabor which unduly added to the total cost of the installation.

It is an object of the present invention to provide a duct-installableheat exchanger having flanges formed thereon similar to the flangesutilized in conventional sheet metal duct work so that the heatexchanger may be mounted in an air conditioner duct system withoutresort to special installation methods such a on-the-job ductfabrication, and/ or special flange formation, and/or the drilling ofmultiple bolt holes.

A further object of the invention is to provide a heat exchanger ofrelatively rigid but lightweight construction to thus adapt theexchanger for installation in conventional sheet metal duct work withoutplacing an excessive mechanical load on the duct walls.

Other objects of this invention will appear from the followingdescription and appended claim, reference being had to the accompanyingdrawings forming a part of this specification wherein like referencecharacters designate corresponding parts in the several views.

In the drawings:

FIGURE 1 is a schematic view illustrating a conventional airconditioning system in which the present invention may be utilized;

FIG. 2 is a view illustrating one embodiment of the invention and takenalong broken line 2-2 in FIG. 3;

FIG. 3 is a sectional view taken along broken line 3-3 in FIG. 2;

. FIG. 4 is a right end elevational view of the FIG. 2 embodiment with apart thereof broken away on line 4-4 in FIG. 2; and

FIG. 5 is an enlarged perspective view of a fragmentary portion of theconstruction shown in FIGS. 2, 3 and 4.

Before explaining the present invention in detail, it is to beunderstood that the invention is not limited in its application to thedetails of construction and arrangement of parts illustrated in theaccompanying drawings, since the invention is capable of otherembodiments and of being practiced or carried out in various ways. Also,it is to be understood that the phraseology or terminology employedherein is for the purpose of description and not of limitation.

In FIG. 1 of the drawings there is shown an air condi-tioning systemhaving aseries of air-treating devices located in the area designatedgenerally by numeral 12 and having a vertically extending riser duct 14for sup- 3,182,717 Patented May 11, 1965 plying conditioned air tovarious lateral duct sections designated by numerals 16, 18, 20 and 22.In the illustrated arrangement duct sections 16 and 18 are intended tosupply conditioned air to interior rooms of the building, while ductsections 20 and 22 are intended to supply conditioned air to perimeterrooms of the building. Sections 16 and 18 are equipped with conventionalceilingtype air diffusers 24, while sections 20 and 22 are connectedwith under-the-window room conditioner units 26. To provide satisfactorycontrol of the temperature Within the interior rooms each of the ductsections 16 and 18 is preferably equipped with an auxiliary heatexchanger 28 constructed as shown in FIGS. 2, 3, 4 and 5.

Referring to FIGS. 2, 3 and 4, heat exchanger 28 includes a top panel30, a bottom panel 32, a right side panel 34, and a left side panel 36.Each of the side panels is provided with an inwardly turned flange 38which is rigidly affixed to a face portion of one of the top and bottompanels, as by screws or rivets (no-t shown). The various panels areformed of relatively light material such as sheet metal but arerigidified by means of the serpentine coil defined by the varioushorizontal heat exchange tubes and return bends 42. The drawings showheat exchange fins only on the end portions of tubes40, but it will beunderstood that in the actual structure the entire length of each tubeis equipped with heat exchange fins. Preferably the top and bottom panel30 and 32 are equipped with integral ribs 44 which serve both asreinforcement devices and as bafiies to prevent the flowing air fromby-passing the heat exchange fin surfaces.

As shown best in FIGS. 2 and 5, the vertical edges of panels 34 and 36are directed outwardly at 46 and then at 48 toward the plane defined bythe heat exchange tubes 40. In the installed position of heat exchanger28 flange portions 46 abut against flange portions 46a which are formedintegrally with the duct sections 16a and 161), the arrangementpermitting the heat exchanger to be locked in position by sliding theC-shaped members 50 downwardly over the abutting flange areas.

The duct sections 16a and 15b are each provided with a top wall 52,bottom wall 54 and two side Walls 56 and 58, the arrangement being suchthat side walls and 58 align with side panels 34 and 36 of the heatexchanger, while top walls 52 and bottom walls 54 overlap edge areas 60of the corresponding heat exchanger panels. This edge overlapment allowsthe S-shape-d sealing elements 62 to be interposed between therespective walls and panels for insuring a substantially air-tight jointtherebetween.

Heat exchanger 28 is installed as the air duct is being fabricated onthe job site. Thus, assuming that duct section 16a is already in placeand that section 16b is not yet installed, the installation of heatexchanger 28 involves initially installing the'two sealing elements 62on the edges of the top and bottom walls 52 and 54 of duct section 16a.The heat exchanger is then manipulated until edge portions 60 thereofare disposed in the S-shaped sealing elements, after which the C-shapedclamps 50 are manually telescoped downwardly over the oppositely facingflanges 48 and 48a of the heat exchanger and duct section; thisprocedure locks the heat exchanger onto section 16a. The next ductsection 16b may then be installed by positioning the appropriate sealingelements 62 and clamp elements 50 in the manner previously described.

It will be noted that installation of the heat exchanger is accomplishedwithout special on-the-job fabricating operations such as the drillingof holes, cutting of special sheet metal sections, or the like. In thisregard, sealing element 62 and clamping element 50 are conventionalstructures commonly utilized in the installation of sheet metal airconditioning ducts so that the invention may be utilizedwith existingduct work designs.

It is contemplated that the heat exchanger of this invention can beconstructed of various sizes and with various numbers of heat exchangetubes 40. Thus for example, the horizontal distance between panels 34and 36 can in some practical forms vary from about twelve inche to aboutforty-two inches, and the vertical distance between panels 30 and 32 canvary from about six inches to fifteen inches. The gauge of the materialfor panels 30, 32, 34 and 36 can be varied to suit conditions.

The drawings illustrate one practical form of the invention, but it willbe appreciated that variations therefrom can be resorted to withoutdeparting from the spirit of the invention as set forth in the appendedclaim.

I claim:

An air conditioning system comprising two horizontally aligned spacedrectangular ducts, each having a top wall, two side walls, a bottom walland vertical flanges formed on duct side walls extending outwardly fromthe edges of said side walls and then parallel therewith in oppositedirections; a rectangular heat exchanger interposed between the twoducts and including a sheet metal top panel, a sheet metal bottom panel,and two sheet metal side panels having their upper and lower edgeportions aflixed to respective ones of the top and bottom panels; saidside panels being of lesser horizontal dimension than the top and bottompanels 30 that the free edge portions of the top and bottom panelsextend horizontally beyond the limits of the side panels intooverlapping relation with edge portions of the duct top and bottomwalls; each of said side panels lying in the same vertical planes as thecorresponding side walls of the duct sections; each of said side panelshaving vertical flanges extending outwardly from their free edges andthen parallel to the panel surfaces so that the outwardly extendingportions of the panel flanges abut against the outwardly extendingportions of the duct flanges; four elongated S-shaped seal'membersfitted on the over-lapped edge portions of the heat exchanger top andbottom panels and the duct top and bottom walls; four C-shaped clampsslidably telescopically engaging the aforementioned abutting flanges tolock the heat exchanger to the ducts; a series of horizontal finned heatexchange tubes extending between and through the two side panels; fluidconduit means located outside said side panels and operativelyconnecting the heat exchange tubes together for conduction of heatexchange fluid therethrough; said top panel having a generally V-shapedrib formed integrally therewith and extending into close adjacency withthe edges of the fins on the uppermost heat exchange tube to constitutean air bafiie and a reinforcement for the top panel; and said bottompanel having a generally V-shaped rib formed integrally therewith andextending into close adjacency with the edges of the fins on thelowermost heat exchange tube to constitute a baffle and reinforcementfor the bottom panel.

References fitted by the Examiner UNITED STATES PATENTS 641,580 1/00Cummins 285-406 760,216 5/04 Laws 285-407 1,040,442 10/ 12 Shannon285-405 1,817,948 8/31 Smith 165-159 X 2,025,802 12/35 Child -2692,110,024 3/38 Miller 55-267 X 2,153,267 4/39 Morse 55-267 2,319,0625/43 Holmes -65 X 2,354,131 7/44 Larkin 165-144 X 2,475,604 7/49 FriSch165-159 X 2,491,700 12/49 Zwerling 285-406 2,568,278 9/51 Favot 219-2132,752,950 7/56 Coulters 285-406 2,956,587 '10/60 Fisher 285-4073,012,762 12/61 Norris 257-295 3,097,507 7/63 Makuh 165-144 X CHARLESSUKALO, Primary Examiner.

HARRY B. THORNTON, Examiner.

